1. Field of the Invention
This invention pertains to an apparatus for the apportioned release or metered dosing of flowable substances or masses with, in particular, a stationary distributor or drum member having, in cross section, at least a rounded outer region relative to which an endless sleeve is moveable.
2. Discussion of Background and Material Information
In the chemical industry, the food industry as well as other industrial fields, there is a need to apportion or meter flowable substances of differing viscosities, and as a rule subsequently solidifying these portions. With thermoplastic substances it is entirely sufficient to cool down fluid droplets, that is portions thereof, on, for example, a transport belt or band that is arranged below the apparatus. In the food industry it may well be desired to subsequently, for example, to subject these portions to a thermal treatment, such as in a baking oven.
Quite a few apparatuses, for the apportioned release or metered dosing of flowable substances, are known in the art. The operating principle of all these apparatuses is that the substances or masses are conveyed in a flowable state or kept in such a state and a flow stream thereof is interrupted. This interruption of the fluid stream can, for example, be accomplished in accordance with U.S. Pat. No. 3,208,101 in that a discontinuous fluid stream is produced via the use of a gear pump. After separation of the fluid stream into individual portions, these portions are received on a movable receiver area that is located underneath the substance exit or is received by other transport means, such as for example a gas stream, a fluidized bed or the like.
A further apparatus for the apportioning of flowable masses is described in U.S. Pat. No. 2,979,764 and utilizes a container which holds a flowable mass. This container, which is circular in cross section, includes a lower frontal area having a plurality of bores. Rotating within this container is a blade or impeller which alternately opens and closes the openings so that, depending upon the viscosity of the fluid and the rotational speed of the impeller, the amount or size of the individually released or metered portions is so determined.
European Patent Publication No. 0,145,839 describes a further apparatus for the apportioned or metered release of flowable masses. Herein, a container, circularly-shaped in cross section, is utilized, around which an additional circularly-shaped drum is rotatable adjacent to the outer surface of the container. This container has an approximately horizontal axis and has, on its lower portion, an exit opening for the masses. This exit opening includes an exchange or distribution piece which includes a slot-shaped opening that cooperates with the outer cylinder and which itself is fed or supplied with the mass via a large number of bores arranged in rows. When using differing viscosities, or during obstructions or breakdowns, the distribution piece cooperating with the cylinder can be exchanged, for example, for one having bores of a smaller diameter or for cleaning purposes.
Disadvantages of the known apparatuses are that adaption for differing viscosities can only be achieved with an increase effort and with extended down times of the apparatus. In addition, as is known, the viscosity of such masses is greatly dependent upon their temperature, wherein even if the masses enter into the apportioning apparatus at a very exact predetermined temperature, it is, in part, difficult to control the cooling within the apparatus.
The known substance distributors or drum members are constructed so that high additions of heat can, due to geometric reasons, be added only with difficulty. Too high a temperature, such as for example of heat exchange media, must be avoided since, as is known, the substances to be apportioned, have low heat conductivities whereby, on one hand a high temperature gradient is caused within the flowing stream of substances while, on the other hand, in the immediate heat transfer areas decomposition of the substances to be apportioned can occur.